Log barker refuse-reducing mechanism



Oct.` 27, 1970 P. J. cl-:RVENAK 3,536,265y

Los BARKER REFUSE-REDUCING MEcHANsM 4Filed March 5o, 1967 2 sheets-smet 1 V l EH'N" r United States Patent() 3,536,265 LGG BARKER REFUSE-REDUCING MECHANISM Peter J. Cervenali, Seattle, Wash., assignor to Nicholson Manufacturing Company, Seattle, Wash., a corporation of Washington Filed Mar. 30, 1967, Ser. No. 627,067 Int. Cl. B02c 18/06, 23/02 U.S. Cl. 241-51 2 Claims ABSTRACT OF THE DISCLOSURE The rotary ring of a log barker has a aring mouth carrying limb-cutting bits in radial planes. Hooked ends of swinging arms rotated around a log as it is moved lengthwise scrape off the bark. Bark and limb pieces fall into a hog having stationary shearing bars cooperating with rotary shearing bars carried above a plate rotating about a vertical axis. Hogged material dropping through apertures in the plate is swept out of the casing by vanes carried by the rotor.

A principal object of the invention is to comminute discrete fragments of bark and limb refuse removed from a log passing through a barker which can be spread as a mulch or transported readily for disposal.

An additional object is to remove limbs from logs being barked more readily and effectively and with less interference with the barking operation than has been experienced previously.

Another object is to remove bark and limb refuse effectively from a log barker so as to eliminate the necessity of cleaning the barker periodically.

It is also an object to utilize the present mechanism in lieu of a refuse conveyor located beneath a log barker.

More particularly, the invention relates to an improved type of limb and knot paring mechanism having inclined bits with an obtuse-angled cutting edge. A refuse hog beneath the barker includes a bridge carrying stationary cutting bars offset from radial positions toward approaching rotary shearing bars, the shearing edges of which rotary bars preferably are offset forwardly in their direction of rotation from radii of the hog rotor. The bogged material drops through apertures in the hog rotor immediately ahead of the rotary shearing bars. Radial vanes varried by the rotor sweep the hogged material around the lower portion of the rotor and out through a tangentially-located discharge port.

FIG. 1 is a longitudinal vertical section through a log barker and refuse-reducing mechanism of the present invention.

FIG. 2 is an elevation of the barker ring assembly viewed from the discharge side, with parts broken away, and FIG. 3 is a corresponding elevation of the barker ring assembly viewed from the feed side.

FIG. 4 is an enlarged vertical longitudinal section through the barker ring assembly.

FIG. 5 .is a detail bottom plan of a portion of a limb cutter bit taken on line 5 5 of FIG. 4, FIG. 6 is a detail section on line 6-6 of FIG. 5, and FIG. 7 is a section on line 7-7 of FIG. 5.

FIG. 8 is a horizontal section taken along line 8-8 of FIG. 1, showing the refuse hog.

Patented Oct. 27, 1970 ice FIG. 9 is a top perspective of a fragmentary portion of the refuse hog.

The refuse-reducing mechanism of the present invention can be applied to various types of rotary ring log barkers, representative examples of which are shown in Nicholson Pat. 2,802,494 and in FIGS. 1, 2, 3 and 4, in particular, of the drawings of this application. Logs L are fed length- Wise to such a barker by a feed conveyor 1 and the barked log is withdrawn from the barker by a discharge conveyor 2. The barker ring assembly is mounted on a plate 3 which can be suitably mounted and guided for elevational movement so that the center of the rotary barker ring 4 will coincide with the axis of the log L being barked. The barker ring is rotated around the log by a drive chain 5 engaging a drive sprocket 6 and teeth provided along the circumference of the lbarker ring.

Each log is fed through the throat 7 of the barker ring 4 to be engaged by scraper tips of the barker arms 8 which are mounted on the barker ring by pivots 9. These barker arms are swung in a direction about such pivots to press their scraping ends against the log by hydraulic jacks 10. Pressure of the barking tips of the arms against the log is maintained by air under pressure in expansible air chambers 11 which are in communication with the respective jacks 10. Such log barker mechanism described thus far in detail is not part of the present invention, but is simply representative of a typical rotary ring barker to which the present invention can be applied.

Projecting from the feed side of the rotary barker throat 7 is an annular flange or collar 12 forming a flared mouth through which a log L is moved by the feed conveyor 1 into the barker ring throat 7. The angle between any portion of such mouth in a radial plane and the axis of the barker ring 4 should be between 45 degrees and 60 degrees and preferably is about 55 degrees. O11 the flaring inner face of collar 12 are mounted elongated cutter bits 13 having their lengths disposed substantially in radial planes. These cutter bits are spaced circumferentially of the barker ring substantially equidistantly, and their inner cutting ends project inward beyond the cylindrical surface of the throat 7.

The preferred shape of the cutter bit 13 is shown in detail in FIGS. 5, 6 and 7. Each bit is of trapezoidal cross section, as shown in FIG. 7, having two parallel sides 13a and 13b disposed in planes parallel to the axis of the barker ring, a side 13C perpendicular to such parallel sides and in contiguous engagement with collar 12 and an inclined face 14a. The face 14a of the bit connecting such parallel sides is inclined relative to them in a direction such that the leading side of the bit in the direction of barker rotor rotation is wider than the trailing side of the bit. Consequently, the leading face 13b of the bit and such inclined joining face 14a converge to form an acuteangled cutting edge 15a which preferably is approximately 60 degrees.

The inner end of the bit is beveled to provide an end surface 14b, shown in FIGS. 5 and 6, which will form a cutting edge 15b that is substantially parallel to the axis of the rotary ring. The bevel between the leading face 13b of the bit and the bit end face 14h again is such that the angle of the cutting edge 15b is acute and preferably about 60 degrees. The two cutting edges 15a and 15by intersect to form an obtuse-angled corner 15e, having an angle between degrees and 135 degrees, depending upon the slope of the inner face of collar 12. Such angle preferably is approximately 125 degrees.

As a log L is fed by the conveyor 1 into the mouth of the barker ring as shown in FIG. 1, the cutting edges a and 15b will engage and trim off any branch stubs or other protuberances projecting outward to a distance beyond the circle defined cooperatively by the cutting edges 15b of the several bits. A sufficient number of these bits should be provided to cut such projections effectively, and sixteen of such bits has been found to be a satisfactory number. Disposition of the lengths of the cutting bits substantially in radial planes of the barker rotor parallel to the axis of the rotor provides a strong cutting end, and one which does an effective cutting job. In particular, a long cutting edge is afforded by arranging the cutting edge sections 15a and 15b at an obtuse angle, as shown best in FIG. 6, instead of the cutting edge sections forming a right angle like the cutting edge sections of the cutter bits shown in the prior Nicholson Pat. 2,802,494.

The limb refuse cut by the bits 13 and the bark refuse scraped from the log by the barker arms in the form of discrete fragments `8 falls into the circular pit 16 shown in FIGS. 1 and 8 which is located directly beneath the barker. Across the lower portion of this pit extends a bridge 17 which may be in the form of a channel having its edge flanges extending upwardly. This bridge preferably extends diametrically across the pit so that it serves to support a bearing for the upper end of an upright shaft 18 located centrally of the pit. This shaft carries a hub 19 on which is mounted a rotor disk 20 of a hog.

The upright shaf-t 18 carries a pulley 21 which is connected by several V-belts 2.2 to a drive pulley 23. This drive pulley can be driven by any suitable drive mechanism such as represented by a shaft 24. The size of the pulleys 21 and 23 will be selected in accordance with the speed of rotation of the drive shaft 24 and the speed at which it is desired to have the hog rotor rotate.

On opposite sides and opposite ends of the bridge =1`7 are mounted stationary shearing bars 25, the lower edges of which constitute shearing edges. Movable shearing bars 26 are carried by the rotor plate 20 in positions to coact with the stationary shearing bars 25V as the rotor rotates. In order to effect a slicing relationship rather than a chopping relationship between the movable and stationary shearing bars, such movable and stationary shearing bars are mounted so that the shearing edge of each moving bar approaches the shearing edge of each moving bar approaches the shearing edge of a stationary bar at an acute angle rather than parallel to the shearing edge of the stationary bar. a

To attain such acute-angled relationship of the shearingbar edges, the bridge 17 is made of substantial width and the stationary shearing bars are mounted chordwise on the edges of the bridge toward the approaching movable shearing bars 26. While such movable shearing bars are disposed substantially radially of the rotor disk 20, their shearing edges are shown in FIG. 8 as being located somewhat forward, in the direction of rotor rotation, of the radius which passes lengthwise through the bar, in each instance. Consequently, when the shearing edges of a movable bar and a stationary bar move into shearing relationship as shown in FIG. 9, such edges are disposed at an acute angle.

The rotor plate 20 is spaced downward somewhat from the lower shearing edges of the stationary shearing bars 25 as shown in FIG. 1. Immediately ahead of each movable shearing bar 26, the rotor plate 20` has a slot 27 through it for passage of hogged waste material from above such plate down into the lower portion of the hog. Beneath each movable shearing bar 26 is a vane 218 extending radially of the rotor, which acts to sweep the hogged waste material rotationally within the casing of the hog including an upright circumferential wall 29, preferably of 4 considerably greater extent than the wall of the pit 16, a bottom wall 30' and an annular top wall 31 bridging between the pit and the circumferential wall 2 of 'the hog.

While the number of movable shearing blades and vanes and the speed of their rotation are not critical, it is preferred that there be from three to six of such shearing bars and vanes, four being shown in the drawings as preferred. The speed of rotation of the rotor should be suftciently great as to provide an effective quick shearing action for bark and limb refuse dropping into the hog onto plate 20. The speed of rotation of the vanes 28 should be great enough so that they will be effective to sweep the hogged material out of the hog casing through a discharge opening 312, which opens tangentially of the casing, both by physical contact of the vanes with such material and by the air current generated by such vanes. The force produced on the air by the vanes discharges such air through opening `32 so that air is drawn down through the pit 16 and the slots 27 in the plate 20 and carries the hogged material with it.

To prevent limb and bark refuse from lodging on the bridge 17, it is preferred that it be capped by a ridge cover 33 held in place by bolts 34. The ridge shape of such cover deters accumulation of refuse on the bridge, but in addition, ow of air drawn through the hog by movement of the vanes 28 will tend to sweep downward past opposite sides of the bridge and remove material from the ridge cover.

Because of the air ow through the hog, discrete bark and limb refuse fragments dropping into the hog onto plate 20 is air-borne to a greater or lesser extent. Since such refuse can only pass through the rotor plate 20 by way of the slots 27 immediately ahead of the moving shearing bars 26, the current of air will tend to blow the waste material fragments from the surface of plate 20 against the leading sides of such bars, to feed the discrete wood refuse fragments between the coacting stationary shearing bars 25 and rotary shearing bars 26. Also, rotational movement of the bars 26 will tend to move them against material falling into the hog. The combination of these actions enables the moving shearing bars to force `at least most of the waste material against the stationary shearing bars to reduce the size of the discrete wood refuse fragments farther before it drops through the slots 27. Consequently, the waste material is hogged suiciently iine so that it can be propelled readily from the hog by the vanes 28 through the discharge opening 32, and such hogged material will be suitable for use as a mulch or for other disposal, such as for fuel.

I claim:

1. Refuse-reducing mechanism for a log barker comprising a hog including an upwardly open pit beneath the barker receiving refuse from the barker, a rotor in said pit including a rotary plate having elongated slots therein spaced circumferentially of said plate and having their lengths extending radially of said plate, means mounting said rotor for rotation about an upright axis, moving shearing bars carried by said plate alongside the edges of said slots trailing With respect to the direction of rotor rotation, a stationary shearing bar mounted stationarily relative to said rotor in a position for movement of said moving shearing bars relative thereto to reduce further discrete wood refuse fragments falling into said pit from the log barker, said plate being positioned adjacent to Said stationary shearing bar for feeding discrete wood refuse fragments between said moving shearing bars and said stationary shearing bar, and blower means effecting movement of a current of air from above said plate down- Ward through said plate slots into the portion of said pit below said plate.

2. Refuse-reducing mechanism for a log barker comprising a hog including a pit beneath the barker including an opening receiving refuse from the barker, a rotor in said pit, means mounting said rotor for rotation about an upright axis, moving shearing bars carried by said rotor, bridge means extending diametrically across the opening to said pit, a stationary shearing bar mounted on one edge of said bridge means offset from a radius of said rotor toward said moving shearing bars approaching said stationary shearing bar for movement of said moving shearing bars relative to said stationary shearing bar to reduce further discrete Wood refuse fragments falling into said pit from the 10g barker, and means for feeding discrete Wood refuse fragments between said moving shearing bars and said stationary shearing bar.

References Cited ROBERT C. RIORDON, Primary Examiner lo D. G. KELLY, Assistant Examiner U.S. C1. X.R. 

